Mckenzie SOUTH FORK
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Bull Trout Population Study in the Middle Fork Willamette and McKenzie River Drainage Basins June - November 1994 Stephen D. Hammond Giles C. Thelen Oregon Department of Fish and Wildlife 3150 East Main Street Springfield, OR 97478 November 1994 CONTENTS Page MAINSTEM McKENZIE POPULATION SUMMARY........................................................................................................... 1 JUVENILE SURVEYS: Lower Separation Creek ................................................................................. 2 Upper Separation Creek and Separation Lake............................................... 4 Harvey Creek.................................................................................................. 5 George Creek ................................................................................................. 6 Anderson Creek.............................................................................................. 7 Olallie Creek ................................................................................................... 8 Creek 58 ......................................................................................................... 9 Buck Side Channel ......................................................................................... 10 Sweetwater Creek........................................................................................... 11 ADULT SURVEYS: McKenzie Standard Pool Check ..................................................................... 12 SPAWNING SURVEYS: Separation Creek............................................................................................ 18 Anderson and Ollalie ...................................................................................... 19 SOUTH FORK McKENZIE POPULATION SUMMARY........................................................................................................... 24 JUVENILE SURVEYS: South Fork ...................................................................................................... 25 Elk Creek ........................................................................................................ 28 Roaring River.................................................................................................. 29 French Pete Creek.......................................................................................... 32 ADULT SURVEYS: South Fork ..................................................................................................... 33 Standard Pools ............................................................................................... 40 MIDDLE FORK WILLAMETTE POPULATION SUMMARY........................................................................................................... 45 JUVENILE SURVEYS Beaver Creek.................................................................................................. 46 Chuckle Spring ............................................................................................... 49 Found Creek ................................................................................................... 50 Indigo Creek ................................................................................................... 51 Pioneer Gulch ................................................................................................. 52 Middle Fork Willamette ................................................................................... 53 ADULT/SPAWNING SURVEYS Middle Fork Willamette and Simpson Creek Spawning.................................. 54 Found and Swift Creek Spawning................................................................... 58 North Fork of Middle Fork Willamette Adults .................................................. 61 MAINSTEM McKENZIE POPULATION SUMMARY Historically, bull trout (Salvelinus confluentus) were either a contiguous population ranging from the lower McKenzie River up to Tamolitch Falls and extending up the larger tributaries, or two populations with overlapping distributions and some genetic interchange. If two populations did exist, one may have spawned in the upper reaches of the South Fork and one in the upper reaches of the mainstem. Spawning habitat is thought to be a limiting factor for this populations. Culvert modification to allow migration of spawning adults has been completed on Sweetwater Creek. Modification of the Olallie Creek culvert under highway 126 is scheduled for summer 1995. Angling is also a concern for the bull trout. Catch and release regulations are in effect, and identification signs have been posted at campsites and fishing holes. There is some possibility for a bull trout hybridization with brook trout S. fontinalis above Trail Bridge Reservoir and in the Horse Creek Basin, where a hybrid was identified in 1992 by Forest Service biologists. conducted juvenile surveys in Creek 58, Buck Side Channel and in the Horse Creek basin, including Separation, Harvey, and George Creeks. The 1994 field surveys during the summer have provided important and useful information. Spawning surveys on Anderson Creek were expanded to include the entire stream. Thirty redds were documented, and their depths and water velocities measured. Three redds were observed on Olallie Creek, one of which had two bull trout on it. This is the first time bull trout have been observed spawning in Olallie Creek. Twenty three age 0 bull trout in Olallie Creek that had been transferred there in March 1994. Juvenile bull trout were also transferred to Sweetwater Creek in 1993 and 1994. A night snorkel survey located 11 age 1+ and seven age 0 bull trout all within 50m of the stocking point. Surveys on lower Separation Creek located one 6-8" bull trout. Fish identified last year as bull trout were actually spring chinook. In the Three Sisters Wildlerness, Upper Separation, Harvey,and George Creeks were surveyed, but no bull trout were located. Creek 58 and Buck Side Channel surveys on the mainstem McKenzie also failed to locate any bull trout. Snorkeling the mainstem McKenzie River between Olallie Campground and Paradise Campground may prove to be a useful method to index bull trout populations. It appears that the adult bull trout seem to be staging in the deeper pools in the McKenzie before moving to spawning areas. SEPARATION CREEK (LOWER) 1 DATE: July 12, 1994; 0900- 1400 PERSONNEL: G. Thelen, S. Lewis WEATHER: Sunny 85°F; water temperature 46°F OBSERVATIONS: 1 bull trout - 250mm Chinook fry: 65-75 observed Cutthroat trout (approx. 45) Rainbow trout (approx. 35) NOTES: We surveyed from the 100m below the confluence of Horse Creek and Separation Creek to 1.2 miles up Separation Creek. The water moved at a high velocity through much of the channel, but there were several side channels and margin areas which were prime bull trout habitat, which includes slower water, woody detritus, and good canopy cover. In these areas we observed a bull trout (Fig 1.), several chinook and many cutthroat. Stream habitat consisted of many log jams, woody debris, and root wads. The substrata was made up of large cobble and boulders, with areas of gravel and silt in the slower water. Much canopy cover was provided by the healthy old growth, mixed age stand of fir, hemlock, cedar, and vine maple. We located the bull trout in the second side channel about .3 miles up from the confluence of Separation Creek and Horse Creek. The water velocity here was medium to still, and varied in depth from six-36 inches. This area is covered by a vegetation bridge which provides much cover. We observed the trout about 10 meters up from the downstream side of this sided channel at the beginning of this vegetation bridge. He was in still water in a dark area, so a flashlight was necessary. Five yards downstream from this location on the North bank was an undercut of an old growth cedar which seemed to be prime juvenile habitat. Five chinook fry were observed here and one possible bull trout fry about 35mm in length. Cutthroat were the primary trout observed. Of the 45 observed 20 were below 100mm and 25 were between 100-250mm. The rainbow ranged in sizes between 30-100mm (15) and 100-300mm (20). The 70 chinook observed were between 25-100mm in length. 2 SEPARATION CREEK (UPPER) and SEPARATION LAKE DATE: September 7, 1994; 1900-2200 PERSONNEL: G. Thelen, S. Hammond, (D. Bickford, J. Capurso USFS) WEATHER: Clear, sunny. Water temperature: 8°C OBSERVATIONS: Cutthroat: 25mm - 230mm Sculpin: 50mm - 100mm NOTES: We sampled from where trail 3536 first nears Separation Creek downstream about 600m to the bottom of a large side channel. For lake, just continue on trail to marked lake turn off. The two teams split up at the bottom of a side channel and worked upstream, with Jim and Dave working the main channel and Steve and Giles going up the side channel. They reported that the main channel had swift water and a steep gradient, so not much good habitat in the margins or on the channel was seen - only one nice lateral scour pool with deep undercut banks. There were a few good plunge pools, but no bull trout seen. Their last 200m had log jams, pools, and decent cover and habitat for adults and juvenile bull trout. The side channel we went on had lots of nice rearing habitat for bull trout. There were many margins and side channels of this side channel that provided lots of cover via downed logs, and sunken woody debris. The last 200m here had lots of successive 1.8m - 2.4m deep pools caused by log jams, providing nice spawning gravel at the tail end